FEA cathode experiments for microwave power amplifiers

Summary form only given, as follows. The investigation of a new class of vacuum microelectronic, microwave power amplifiers based on field emitter array (FEA) technology is currently underway at the Naval Research Laboratory. FEAs offer instant activation, higher transconductance and higher current densities than thermionic cathodes and consequently higher performance gridded microwave power tubes should be possible. FEA microwave power amplifiers are attractive for improved vacuum power boosters in the next-generation microwave power module. A twystrode employing FEAs as the cathode is being designed to operate at 10 GHz with 50 W output power and 10 dB gain. FEAs will be used to generate an electron beam of up to 160 mA at 2.5 kV with a magnetic field of 2 to 3 kG. Experiments to characterize this electron beam will be presented. The design of a beam transport experiment, which will simulate the circuit of the twystrode, will be shown. Recent and future FEA experiments to demonstrate the experimental operating parameters of the FEA twystrode will also be discussed.